Synthetic resin containers made from a synthetic resin such as polyester or polyethylene terephthalate (PET) have been widely put into practical use as containers for beverages. A preform that is to be formed into a synthetic resin container by blow-forming can be integrally formed by compression-molding by using a compression-molding machine.
In executing the compression-molding, the synthetic resin in a molten state is extruded through an opening of an extrusion nozzle and is fed to the compression-molding machine by a resin feeder.
FIG. 8A is a plan view illustrating a state where a molten resin 107 is held by a holding unit of a conventional apparatus for feeding resin, FIG. 8B is a plan view illustrating a state where the holding unit is opened, and FIG. 8C is a side view of when FIG. 8A is viewed from a direction of line X-X.
The holding unit 101 is held by rotary means which is not shown so as to move along a rotary track. The holding unit 101 includes a base portion 102 and a pair of holders 103. A semi-cylindrical recessed holding portion 104 is formed in the base portion 102. A cutter 105 is formed at an upper part of the base portion 102, the blade tip thereof protruding upward and aslant in a direction in which it proceeds, and the blade extending in parallel with the radial direction of rotation of the holding unit 101. The pair of holders 103 is rotatably supported by the base portion 102 so as to be opened and closed.
While moving on the rotary track, the holding unit 101 opens the holders 103 as shown in FIG. 8B on the upstream of the die head of the extruder (see FIG. 2 of the embodiment), cuts the molten resin (drop) 107 discharged from the die head by the cutter 105, closes the holders 103 as shown in FIG. 8A to hold the molten resin 107, is conveyed to just over the metal mold of the compression-molding machine, and feeds the molten resin 107 to a female mold of the metal mold.
The following patent document 1 discloses an apparatus for feeding molten resin in which a synthetic resin cut away from an extrusion opening of a die head is held by a holder, and the holder is opened when it is conveyed to just over a female mold of a compression-molding machine to thereby feed the molten resin into the female mold.
Patent document 1: JP-A-2000-108127
Patent document 2: JP-A-2005-059240